/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.catalina;

import java.util.EventObject;

/**
 * General event for notifying listeners of significant changes on a component
 * that implements the Lifecycle interface.  In particular, this will be useful
 * on Containers, where these events replace the ContextInterceptor concept in
 * Tomcat 3.x.
 *
 * @author Craig R. McClanahan
 */
public final class LifecycleEvent extends EventObject {

	private static final long serialVersionUID = 1L;


	// ----------------------------------------------------------- Constructors
	/**
	 * The event data associated with this event.
	 */
	private Object data = null;


	// ----------------------------------------------------- Instance Variables
	/**
	 * The event type this instance represents.
	 */
	private String type = null;

	/**
	 * Construct a new LifecycleEvent with the specified parameters.
	 *
	 * @param lifecycle Component on which this event occurred
	 * @param type      Event type (required)
	 * @param data      Event data (if any)
	 */
	public LifecycleEvent(Lifecycle lifecycle, String type, Object data) {

		super(lifecycle);
		this.type = type;
		this.data = data;
	}


	// ------------------------------------------------------------- Properties

	/**
	 * Return the event data of this event.
	 */
	public Object getData() {

		return (this.data);

	}

	/**
	 * Return the Lifecycle on which this event occurred.
	 */
	public Lifecycle getLifecycle() {

		return (Lifecycle) getSource();

	}

	/**
	 * Return the event type of this event.
	 */
	public String getType() {

		return (this.type);

	}


}
